scholarly journals Energy conservation using high-efficiency electric motors

2012 ◽  
pp. 91-96
Author(s):  
Sergio Roberto Jardim ◽  
Gilmar Barreto
Keyword(s):  
Energy Conservation ◽  
High Efficiency ◽  
Electric Motors

scholarly journals Recent Design Optimization Methods for Energy-Efficient Electric Motors and Derived Requirements for a New Improved Method—Part 1

Proceedings ◽  
2018 ◽  
Vol 2 (22) ◽  
pp. 1400
Author(s):  
Johannes Schmelcher ◽  
Max Kleine Büning ◽  
Kai Kreisköther ◽  
Dieter Gerling ◽  
Achim Kampker
Keyword(s):  
Rare Earth ◽  
Design Optimization ◽  
Energy Efficient ◽  
Degrees Of Freedom ◽  
High Efficiency ◽  
Optimization Problems ◽  
Computing Time ◽  
Optimization Methods ◽  
Electric Motors ◽  
Electric Cars

Energy-efficient electric motors are gathering an increased attention since they are used in electric cars or to reduce operational costs, for instance. Due to their high efficiency, permanent-magnet synchronous motors are used progressively more. However, the need to use rare-earth magnets for such high-efficiency motors is problematic not only in regard to the cost but also in socio-political and environmental aspects. Therefore, an increasing effort has to be put in finding the best design possible. The goals to achieve are, among others, to reduce the amount of rare-earth magnet material but also to increase the efficiency. In the first part of this multipart paper, characteristics of optimization problems in engineering and general methods to solve them are presented. In part two, different approaches to the design optimization problem of electric motors are highlighted. The last part will evaluate the different categories of optimization methods with respect to the criteria: degrees of freedom, computing time and the required user experience. As will be seen, there is a conflict of objectives regarding the criteria mentioned above. Requirements, which a new optimization method has to fulfil in order to solve the conflict of objectives will be presented in this last paper.

Numerical and experimental investigation of flow phenomena in rotating step-holes for direct-spray-cooled electric motors

2020 ◽  
pp. 146808742091804
Author(s):  
Christopher Beck ◽  
Jürgen Schorr ◽  
Harald Echtle ◽  
Jasmin Verhagen ◽  
Annette Jooss ◽  
...  
Keyword(s):  
Flow Rate ◽  
Electric Motor ◽  
Rotational Speed ◽  
High Speed ◽  
High Efficiency ◽  
Volumetric Flow Rate ◽  
Dielectric Fluid ◽  
Electric Motors ◽  
Test Environment ◽  
Operating Points

Despite their high efficiency, electric motors are thermally limited in some operating points by several types of losses. Whenever temperature–critical components threaten to overheat, the performance is reduced for component protection (derating). The use of a suitable cooling concept may reduce the derating. The design of efficient cooling concepts of electric motors in traction drives with increased power densities is challenging, caused by the fact that the heat releases in the components vary considerably with the operating point. One option to reduce the temperatures is to place the heat sinks close to heat sources. Therefore, direct spray cooling with nozzles located in the rotor shaft is often used for cooling the end windings. The dielectric fluid (e.g. oil) is introduced into the mainly air-filled interior of the electric motor. In the following study, the behavior of the jet in the rotating step-holes at different volumetric flow rates is examined. To carry out the investigation, a new test rig and a novel optically accessible electric motor were designed. In this specifically designed test environment, the shape of the jets of different operating points is investigated by direct high-speed visualization. The cinematography setup is made of a four-light-emitting diode system in combination with a high-speed camera. A combined approach of experiment and simulation is used to find basic mechanisms of spray formation produced by rotating step-holes. Depending on the volumetric flow rate and the rotational speed, the direction of the oil jet gets more curved in relation to the rotating nozzle after exiting the small bore. If the deflection is large, the jet impinges on the wall of the large bore before reaching the end of the nozzle. The jet formation at the exit of the step-hole is mainly driven by the divergent forces in the liquid caused by impingement and the counteracting Coriolis force. Depending on the volumetric flow rate with constant rotational speed, different cross-sectional shapes of the jet at the exit are observed. These characteristic shapes can be grouped as a round undisturbed jet, strands with a connecting lamella and a C-shaped cross-section.

scholarly journals Policy Performance of Green Lighting Industry in China: A DID Analysis from the Perspective of Energy Conservation and Emission Reduction

Energies ◽  
2020 ◽  
Vol 13 (22) ◽  
pp. 5855
Author(s):  
Kan Wang ◽  
Li Lei ◽  
Shuai Qiu ◽  
Sen Guo
Keyword(s):  
Energy Conservation ◽  
Emission Reduction ◽  
High Efficiency ◽  
Evaluation Model ◽  
Policy Support ◽  
Policy Framework ◽  
Current Status ◽  
Policy Performance ◽  
Lighting Industry ◽  
The Difference

As a component of China’s strategic emerging industries, green lighting is an important industry supporting the high-quality and high-efficiency development of China’s economy, and is also an important way to achieve energy conservation and emission reduction. At present, China has basically established a policy framework to promote the development of green lighting industry, but there is no empirical evidence on the performance of existing policies on energy conservation and emission reduction. Based on the development status of China’s green lighting industry, this paper sorts out the milestones of China’s green lighting industry policy and the current status of the framework of the existing green lighting industry development policies, constructs a policy performance evaluation model for China’s green lighting industry based on the difference-in-difference (DID) model, and evaluates the implementation effects of green lighting industry policies in China from the perspective of energy conservation and emission reduction. The empirical results of China’s 85 cities show that the implementation of green lighting industry policies has significantly promoted regional energy conservation and emission reduction. Finally, this paper puts forward targeted policy recommendations to provide policy support for the transformation of China’s green lighting industry from “large” to “strong”.

Applications of Rigid Polyurethane Foam Insulation Materials in Architectural Energy Conservation

2012 ◽  
Vol 608-609 ◽  
pp. 1783-1785
Author(s):  
Xiao Ying Zhang ◽  
Guo Hui Wang ◽  
Dan Liu ◽  
Ying Wang
Keyword(s):  
Energy Conservation ◽  
Polyurethane Foam ◽  
Thermal Insulation ◽  
Small Proportion ◽  
High Efficiency ◽  
High Price ◽  
Rigid Polyurethane Foam ◽  
Smoke Toxicity ◽  
Application Development ◽  
Paper Briefly

This paper briefly introduces the main properties and four systems of rigid polyurethane thermal insulation foam intended for use in buildings for energy conservation purposes, and application development at home and abroad. Although the applications of polyurethane are widespread in architectural energy conservation, there are some problems just as high price, smoke toxicity, fire safety and so on thus it still occupies a small proportion in buildings for energy conservation purposes. It is no doubt that the function with high efficiency of thermal insulation, fireproof and low smoke density of rigid polyurethane foam conservation products is our goal.

Energy Saving Studies in Industrial Facilities

2008 ◽  
Author(s):  
Mehmet Kanoglu ◽  
Ilker Karabay ◽  
Ibrahim Dincer
Keyword(s):  
Energy Consumption ◽  
Energy Conservation ◽  
Energy Saving ◽  
Energy Use ◽  
High Efficiency ◽  
Industrial Sector ◽  
Total Energy Consumption ◽  
Industrial Facilities ◽  
Conservation Measures ◽  
Energy Conservation Measures

Efficient energy use is critical for the success of any industrial facility since reduced energy consumption through energy conservation/saving programs can benefit not only consumers and utilities, but society in general as well. In particular, reduced energy consumption generally leads to reduced emissions of greenhouse gases and other air pollutants into the environment. It also helps reduce the operational costs in the facility. There is a strong need to take some energy saving measures in every plant/ facility. Although these may be quite diverse, some of these measures include thermal insulation, use of more efficient equipment, heat recovery systems, high efficiency lighting, changing the fuel, reducing the cost of compressed air, and enhancing productivity. In this study, some certain energy conservation measures are considered for assessing a packaging film manufacturing facility in Gaziantep, Turkey. Taking advantage of dry and hot climates of the city, cooling compressor inlet air by evaporative cooling technique is also assessed. Our investigation shows that there is a huge room for energy conservation measures. The total savings potential are expected to be 869,350 YTL (about $725,000) representing about 16% of the total energy consumption. The payback periods for the identified measures are justified. We believe that the results are typical rather than exceptional for the industrial sector in Turkey.

scholarly journals Development of a High Efficiency Induction Motor and the Estimation of Energy Conservation Effect

2014 ◽  
Vol 55 (3) ◽  
pp. 138-143 ◽  
Author(s):  
Minoru KONDO ◽  
Minoru MIYABE ◽  
Shinichi MANABE
Keyword(s):  
Energy Conservation ◽  
Induction Motor ◽  
High Efficiency

Application of Pulse Electrocoagulation to Dye Wastewater Treatment

2011 ◽  
Vol 233-235 ◽  
pp. 444-451 ◽  
Author(s):  
Yi Min Chen ◽  
Bao Xue Zhou ◽  
Long Hai Li ◽  
Yong Hiu Song ◽  
Jin Hua Li ◽  
...  
Keyword(s):  
Energy Conservation ◽  
High Efficiency ◽  
Electrical Energy ◽  
High Energy ◽  
Dye Wastewater ◽  
Treatment Efficiency ◽  
Efficient Technology ◽  
Iron Electrodes ◽  
High Level ◽  
High Energy Consumption

Electrocoagulation (EC) has been proven by a substantial number of studies to be an efficient technology to remove organic pollutants from wastewater. Nevertheless, the high energy consumption of this technology inhibits its extensive application. The objective of this work is to investigate the feasibility of electrical energy conservation and high efficiency by using Pulse Electrocoagulation (PE). PE, a combination of a pulsing technique and EC, was proposed in an attempt to treat the dye wastewater. The results demonstrated that PE, as compared with DCE (direct current electrocoagulation), resulted in up to 51.66% energy conservation by using two iron electrodes as anode and cathode. Moreover, this high energy conservation was obtained during a high level of treatment efficiency: 99.62% of color removal and 91.15% of COD removal for 1000 mg L-1 4BS solution in a short electrolyzing time of 15 mins.

THE PERFORMANCE OF CONDENSER UNDER DIFFERENT VEHICLE SPEEDS

2013 ◽  
Vol 21 (02) ◽  
pp. 1350013 ◽  
Author(s):  
CHIH-CHIU SHEN ◽  
JAU-HUAI LU
Keyword(s):  
Electric Vehicle ◽  
Electric Vehicles ◽  
Air Conditioning ◽  
High Efficiency ◽  
Cooling Capacity ◽  
Vehicle Speed ◽  
Air Conditioner ◽  
Electric Motors ◽  
No Emission ◽  
Air Conditioning System

Due to the concern in energy shortage and environmental protection, electric vehicle is considered to be a substitute for the conventional gasoline-powered vehicles due to its characteristics of high efficiency and no emission. However, the load of air conditioning causes a serious problem for electric vehicles, especially in tropical and subtropical areas. The compressor of conventional air conditioning system is driven by engine and its speed is thus coupled to vehicle speed. In electric vehicles, the compressor is driven by electric motors and compressor speed could be decoupled to vehicle speed. This mechanism provides an opportunity to improve the energy efficiency of electric vehicle since the operation of air conditioning system may be independent of vehicle speed. The purpose of this paper is to find out the electric fan operation model as vehicle speed is varied. This paper was to establish a theoretical model for the condenser of automotive air conditioner and to conduct simulation to evaluate the effect of vehicle speed on the cooling capacity and sub-cooling of condenser. Results of simulation demonstrated that vehicle with 6 km h-1 speed has the 5°C of sub-cooling at 0.0266 kg s-1 of refrigerant flow rate and the cooling capacity was 4.93 kW. In this study, an increase of 16.6% in cooling capacity can be reached as the speed of vehicle was raised from 6 to 110 km h-1 and can promote the sub-cooling to 19.5°C. It was also found that the cooling capacity of air conditioner is extremely sensitive to vehicle speed while the vehicle is running at low speed. Furthermore, increases in the vehicle speed resulted in reduction of the length of superheat region from 17.5 to 8.5 cm. Finally, a correlation among these variables and the simulated cooling capacity was obtained in this study, enabling the relevant researchers to evaluate automotive air conditioner performance under different vehicle speeds more easily.

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